Longitudinal shaft assemblies represent a stiff structure in the motor vehicle which must be designed, in particular, with a view to its crash behaviour. A primary concern when designing longitudinal shaft assemblies is therefore to ensure that no component of the longitudinal shaft assembly becomes detached from the longitudinal shaft assembly in such a manner that it would penetrate other regions of the vehicle. Thus it must be avoided, in particular, that parts of the longitudinal shaft assembly penetrate the passenger compartment and/or the fuel tank, whereby additional danger of injury to the vehicle occupants or fire risk through escaping fuel could occur.
Such longitudinal shaft assemblies have at least a first shaft and a second shaft by means of which the driving force of the motor vehicle is transmitted. In this case the shafts are connected to one another by means of a ball-type constant velocity joint which preferably has a limited range of axial displacement. Through the axial displacement range of the ball-type constant velocity joint, movements of individual components of the longitudinal shaft assembly or of the motor vehicle in the longitudinal direction of the vehicle are compensated. In addition, deflections of the shafts with respect to one another arising from the ball-type constant velocity joint are compensated by articulation of the constant velocity joint.
As a rule, a central bearing arranged on at least one shaft is provided to mount the longitudinal shaft assembly to the motor vehicle. This bearing, which is necessary to guide the longitudinal shaft assembly, additionally serves to damp and reduce vibrations arising in the longitudinal shaft assembly.
Longitudinal shaft assemblies of the aforementioned type must be designed for the particular application, in particular with regard to the driving force to be transmitted. Further parameters include the overall length of the longitudinal shaft assembly, the space available in the motor vehicle, the weight of the motor vehicle and crash requirements.